ABC News(WASHINGTON) -- President Donald Trump in a letter directly to North Korean leader Kim Jong Un on Thursday announced that he is canceling the much anticipated nuclear summit, calling it a "truly sad moment in history." "Sadly, based on the tremendous anger and open hostility displayed in your most recent statement, I feel it is inappropriate, at this time, to have this long-planned meeting. Therefore, please let this letter serve to represent that the Singapore summit, for the good of both parties, but to the detriment of the world, will not take place." The president's letter comes after North Korea issued a statement calling Vice President Mike Pence a "political dummy" for comments he made suggesting that the so-called Libya model could be applied to North Korea if Kim doesn't make a deal with President Trump and threatening to pull out of the summit.At the U.S.'s urging, under the leadership of Col. Muammar el-Qaddafi, Libya, nixed its early-stage nuclear program. Years, later he was ousted and killed with help from NATO-backed troops."Whether the U.S. will meet us at a meeting room or encounter us at nuclear-to-nuclear showdown is entirely dependent upon the decision and behavior of the United States," the North Korean statement read.